John thomson



. (No Model.)

J. THOMSON.

BBNGH VISE.

NQ. 255,700. Patented Mai. 28,1882.

UNITED STATES PATENT OFFICE.

JOHN THOMSON, OF BROOKLYN, NEW YORK.

BENCH-VlSE.

SPECIFICATION forming part of Letters Eatent No. 255,700, dated March28, 1882. Application filed January t), 188:2. (No model/l .To all whomit may concern: Be it known that I, JOHN THOMSON, a citizen of theUnited States, residing in the city ofBrooklyn, county of Kings, andState of New York, have invented certain new and useful Improvements inBench-Vises, fully described and represented in thefollowingspecification and the accompanying drawings, forming a part ofthe same.

This-invention relates to what are known 'as parallel screw-Vises, andhas for its object the production of a vise of this class which will bestronger, lighter, more rigid and compact in structure, which can morequickly and readily be made to accommodate itself to the varying sizesof the work to be clamped, and

In said drawings, Figure 1 is a sideeleva tion of a parallelvviseembodying this invention, thejaws being broken away inplaces to show theinterior mechanism. Fig. 2 is aplan view, and Fig. 3 a front elevation,of the same.

. Fig. 4 is a front elevation of the back jaw, the

ratchet-rod being shown in section and the crank-arm of the pawl beingremoved. Figs. 5 and6 illustraternodifitzationsto behereinafter referredto.

As is usual in screw-Vises of this class, the

jaw 1 is secured to the bench or other solid support, and the jaw2iscaused to move bodily to and from the jaw 1, the two always remain ingsubstantially parallel.

In screw-visesof this class as heretofore constructed the screw, whichis of considerable length, passes loosely through the movable jaw andworks in a nut formed in or j ust' in rear of the fixed jaw, and thejaws are moved to and fromeach other only by the action of the screw.This means of openin g and closing the jaws is necessarily slow, andwhen, as is frequently required,t-he spread of the jaws has to bechanged considerably, it occasions delay and useless expenditure oflabor. To avoid this slow process and to provide for the rapidadjustment of the jaws to work of varying sizesthescrew 3' is madeshorter thanusual and worksin a nut, 4, tapped to a suitable may bepolygonal, slides freely back andforth in a bearing, 6, formed in thejaw 1, the end which is formed to constitute the nut 4entering acorresponding bearing, 7, formed-in the jaw 2. One side of the slidingbar 5 is preferablyflattened, as clearly shown in Fig. 4, and isprovided with a series of ratchet-teeth, as 8, which engage with apawl,9, that is housed in a recess, 11, formed in jaw 1, just below thebearing of rod 5, said pawl projecting from a stud, 10, that extendsinside of the jaw-body, where it carries a crank-arm, 13. The paw] isheld in engagement with the ratchet by a spring, 12, but can be readilywithdrawn from such engagement, when desirable, bya proper movement ofsaid crank-arm 13.

From the foregoing it will readily bc apparcut that by a proper movementof the pawl 9 the jaws may be quickly adjusted with respect to eachother by a sliding movement, and when so adjusted the slow and powerfulmovement necessary to secure the work firmly may be accomplished bytheusual rotary movement of the screw. Thus when the jaws require to beadjusted to receive a piece of work of large dimensions, it is onlynecessary to operate the crank-arm 13, so as to disengage the pawl 9from being set at the required relative distance apart, the crank-arm 13is released to permit the pawl to engage with the ratchet and'sus- Vpend any further outward movement of the bar 5. 1f the screw 3 is nowproperly rotated,

it will be drawn into the nut 4 in the end of rod 5, thus slowlyshortening said rod; and as its fixed collar 15 impinges against thehear. ing 16 of the jaw 2, and the pawl 9 at the same time locks the jaw1 to the rod 5, the shortening of said rod will consequently cause thejaws to be slowly and powerfully drawntogether to clamp the work veryfirmly between them. Since in this vise as ordinarily operated the screw3 is required only to move the jawa very short' distance, it can be madeof fine pitch, thus making the vise very powerful in its nipping action.The reverse movement of the screw to release the nip upon the workwillbe sufficient to provide for the subsequent nippingaction, while itfrees the parts to admit of the quick adjustment. Sufficient amplitudeof action is given the screw in allcases, so that with thejaw set toapproximate a certain average of work it may then be operated, as in thecase of an ordinary screwvise, by means of the screw alone. This featureadapts the vise for clamping a yielding substance, as a coiled spring,which would not be the case were this action limited.

When the rod 5 is of round form it is prevented from turning with thescrew by means of the spline or feather 17, which extends into a grooveor, slot, 18, in thejaw 2.

The screw 3 is prevented from being withdrawn from jaw 2, either whenits action is reversed or when the jaws are being separated, by the cap19, placed outside of collar and secured by screws to thejaw 2. The cap19 is placed upon the hub of screw 3 before securing the hand-lever toposition, and hence is removable from the hub of the screw only bydetaching said hand-lever.

The jaws 1 2, as will readily be seen, can be brought together to adaptthe vise to nip a piece of work of small size by simply pushing jaw2.inward, the ratchet-teeth in such case sliding idly past the end ofthe pawl. By this construction the screw and strain bearing surfaces areincased, and hence protected from dust and filings. The jaws 1 2 aresustained in their parallel relation to each other both vertically andhorizontally by the guide-rods 20 21, which are rigidly set in the jaw2, but which slide freely in bearings 22 23 in the jaw 1.

When a piece of work or other material that may yield unevenly underpressure is being clamped the strain upon the parts tends to throw thejaws out of their vertical parallel relation, the direction of theforces exerted in such case being indicated by the arrows, Fig. 1.

Therods 20 21 are located at a distance from rod '5, from center tocenter considerably. greater than the distance of the clamping-faces ofthe jaws from said rod, and, being made of hard rolled wrought-iron orsteel and having, bearings of considerable extent in the jaw 1; they aresufticientl y rigid to successfully resist the strain to which theyaresubjected and substantially preserve the parallel relation of the jaws.

It should be borne in mind that the clamping-faces, or the center of thepart being clamped, constitutes a fulcrum acted upon by the. power atrod 5, and restrained from vertical deflection by the rods 20 21.

When a piece of work is clamped out of center, or at the extreme edgesof the jaws, the tendency (in addition to that of the vertical parallel)is also to throw the jaws out of'their parallel relation horizontally,the direction of this strain being indicated by the arrows in Fig. 2.Such a double or cross strain is the severest test to which a vise issubject, causing an additional torsional effect upon the jaws. It willreadily be seen that this tendency is counteracted by the two slide-bars20 21 much more effectually than by the single large bar heretoforeused, even though the former are of small size and contain considerablyless material than the latter.

In Figs. 5 and (i is shown a friction-clutch which may be substitutedfor the pawl 9 and ratchet 8. The clutch 24 is fixed upon a shaft, as10, the same as the pawl 9, and is thrown out of engagement with the rod5 in the same manner. The clutch is, however, set so that it bearsagainst the solid wall of the recess 11, instead of entirely upon theshaft 10, as does the pawl.' When the rod 5 is slid in the direction forclosing the jaws the clutch is not called into action; but upon anyattempt to move the rod in the opposite direction it is locked by theaction of the clutch.

Fig. G shows the end of the clutch 24 as made slightly concave, so as tocome into contact with more of the surface of rod 5.

If it is found desirable, the end of the clutch and the lower side ofthe rod may be serrated or milled, so as to insure a positive bite.between them.

It will readily be seen that the double guiderods 20 21 may be used toadvantage in vises provided with an ordinary screw or in vises operatedby other means than a screw, and also that the devices herein describedfor operating the jaws may be used to advantagein vises having only asingle guide-rod or a tailpiece cast solid with one of the jaws.

What I claim is- The combination of thejaws, as 1 2, the guide-rods 2021, rigidly attached to one of thejaws and sliding in the otherjaw, thesliding rod, as 5, having bearings in both jaws, and provided with thenut, as 4, and ratchet, as 8, with the pawl, as 9,"and screw, as 3, and

means for operating said pawl and screw, substantially as described.

2. The combination of the jaws, as 1 2, a guide-rod rigidly secured toone jaw and sliding in the other, a sliding rod, as 5, having bearingsin both jaws, a mechanism for looking said rod 5 in different positionsin one of the jaws, and a screw and nut, as 3 4, and means for operatingsaid screw and nut, sub stantially as described.

3. The combination of the jaws, as l 2, a guide-rod rigidly secured toone jaw and sliding in the other, a round sliding rod, as 5,hav ingbearings in both jaws and provided with a feather, as 17, for holding itin position, a mechanism for locking said rod 5 in different positionsin one of the jaws, a screw and nut, as 3 4, and means for operatingsaid screw and nut, substantially as described.

4. The combination of the jaws, as 1 2, a

guide-rod rigidly secured to one jaw and slidmy hand in the presence oftwo subscribing ing in the other, the sliding rod, as 5, havingwitnesses. bearings in both jaws, and provided with the nut, as 4, withthe screw, as 3, having shoul- JOHN O 5 der 15, and the cap, as 19,substantially as de- Witnesses:

scribed. r I J. A. HOVEY,

In testimony whereof I have hereunto set A. N. JASBERA.

